Power line communications (PLC) technology is aimed at transmitting digital data by utilizing the existing infrastructure of the electrical grid. It allows, in particular, remote reading of electric meters, exchanges between electric vehicles and the recharging terminals and also management and control of energy networks (smart grid). PLC technology incorporates, in particular, narrow band power line communication (N-PLC) which is generally defined as a communication over an electrical line operating at transmission frequencies of up to 500 KHz. N-PLC communication thus generally uses the frequency bands defined in particular by the European committee for electrotechnical standardization (CENELEC) or by the Federal Communications Commission (FCC). Thus, if the CENELEC A frequency band (3-95 kHz) is considered, the transmission frequencies are situated between 35.9375 and 90.625 KHz for the PLC-G3 standard.
The signals conveyed by PLC and received by the receiver result from a combination of several signals having followed within the transmission channel (the electrical line) several propagation routes or paths each having its own time delay and its own attenuation (the transmission channel is a multi-path transmission channel). The overall performance of a receiver depends greatly on the quality of its channel estimation, i.e. on the estimation of the transfer function of this channel. Contemporary receivers, compatible with the PLC-G3 standard, are suitable for performing a channel estimation when the latter is linear and time invariant (LTI: “Linear Time Invariant”), by using two orthogonal frequency-division multiplexing (OFDM) symbols to estimate the channel transfer function.